Just because someone is confident about their own weird interpretation of something on the Internet does not make it true.

I (and lot of people I know) use elipsis in writing all the time... usually to indicate a pause or change of direction from the previous thought. If I am in a hurry to get technical details down in text and off to some team, worrying about 100% correct proper writing style is time and luxury that I almost NEVER have.

And besides, unless you work in a law office or something, email is NOT a formal communications method. Grammar and spelling should be within acceptable limits but not a deal-breaker. Otherwise you'd be skating near the principle of judging a book by its cover which would be very un-woke.